Washington ? Consumer prices rose by 0.3 percent in January, the biggest one-month increase in nine months, as gasoline and other energy prices shot skyward, reflecting worries in global oil markets over what war in Iraq would do to supplies.

The Labor Department said Friday that the January increase in its Consumer Price Index, the most closely followed inflation gauge, was the biggest since a 0.4 percent advance last April. In November and December, prices had edged up just 0.1 percent.

Traders take bids and offers on crude oil at the New York Mercantile Exchange. Consumer prices jumped by 0.3 percent in January, the largest increase in nine months.

Virtually all the price pressure occurred in the energy sector. The costs of a variety of other items from clothing and food to new cars and airline tickets actually fell in January, underscoring that the weak U.S. recovery is making it hard for companies to charge more for their goods.

The 0.3 percent rise in consumer prices last month was dominated by a 4 percent surge in energy prices, the biggest spurt in this area since last April. Prices of gasoline at the pump jumped by 6.6 percent, the biggest increase since a 9 percent rise last April. So far in February, gasoline prices have continued to rise, with one nationwide survey putting the average currently at $1.66 per gallon, up 22 cents since the beginning of the year.

Outside of gasoline, home heating oil costs were up 8.6 percent last month, the biggest increase since August 2000.